X-RAY DISCOVERY OF A HOT PG-1159 STAR, RX-J0122.9-7521

Authors
COWLEY AP SCHMIDTKE PC HUTCHINGS JB CRAMPTON D
Citation
Ap. Cowley et al., X-RAY DISCOVERY OF A HOT PG-1159 STAR, RX-J0122.9-7521, Publications of the Astronomical Society of the Pacific, 107(716), 1995, pp. 927-930
Citations number
25
Categorie Soggetti
Astronomy & Astrophysics
Journal title
Publications of the Astronomical Society of the Pacific
ISSN journal
00046280 → ACNP
Volume
107
Issue
716
Year of publication
1995
Pages
927 - 930
Database
ISI
SICI code
0004-6280(1995)107:716<927:XDOAHP>2.0.ZU;2-V
Abstract
The supersoft X-ray source RX J0122.9-7521 has been optically identifi ed with an extremely hot PG 1159 star, Its spectrum shows high-excitat ion emission lines from which we estimate T(eff)similar to 140,000 K a nd log g similar to 7. Limited photometry taken during six nights show s no conclusive variability, but we cannot rule out short-period, low- amplitude pulsations (P<5 min) as are found in some PG 1159 stars. The re is some evidence for variations in the emission-line strengths, but higher-quality spectra are needed to confirm this.